package lab02.test28;
import java.util.Scanner;
public class Circle {
    public static void main(String[] args) {
        System.out.println("please input one Double");
        Scanner sc=new Scanner(System.in);
try {
    double R=sc.nextDouble();
    System.out.println("圆形的面积为："+3.14*R*R);

}
catch (Exception a){
    System.out.println(a);

}

finally {
    Scanner input=new Scanner(System.in);//重新建立一个输入对象，
    // 不能使用原来的输入对象，否则会报错
        double R=input.nextDouble();
        System.out.println("圆形的面积为："+3.14*R*R);
    }
    }
}
